- Program Areas
- Installation Energy and Water
- Environmental Restoration
- Munitions Response
- Resource Conservation and Resiliency
- Weapons Systems and Platforms
PFAS-Free Foam / Compressed Air Foam, Fire Suppression Alternative
David Munroe | ACAF Systems
The objective of this project is to provide test data to support Compressed Air Foam (CAF), a foam making process when used with Fluorine-Free Foams (FFF) to be effective in firefighting for aviation and naval application and can meet all fire performance requirements of the MIL F 24385 test protocol. Fluorine-Free Foams offer a better environmental firefighting solution than aqueous film forming foam (AFFF) but often have difficulty in meeting the fire performance requirements of MIL SPEC. Rate of application is often required to be greater than that of traditional AFFF. An alternative foam making process using CAF will strengthen a FFF product by generating a higher quality finished foam product. The results are a FFF that will meet the fire performance of MIL SPEC at rates of application equal to or less than what are required today. By producing FFF as CAF a solution is possible to replace AFFF C8 and C6 use without giving up performance. Both Aviation and Naval applications may benefit environmentally and performance wise from systems and solution design around FFF/CAF foam making process.
CAF, a foam making process, is a mechanical method used to produce a finished foam. In the process compressed breathing air or nitrogen gas is injected into the foam / water solution in a device known as a mixing chamber. The resulting product is a homogeneous foam of very tiny bubbles. It is this bubble structure that gives CAFs the ability to do what it does. Design of the mixing chamber is critical to quality of foam. Unique to CAF is a uniform bubble size finished foam that is created and may be delivered through pipe systems and applied by conventional foam applicators both type II and III devices. The project research program is to optimize the performance of FFF/CAF to the requirements of MIL-F-24385 at MIL SPEC rates of application and lower using several FFF manufactured foams. A further study shall be made to compare the performance of FFF/CAF to that of conventional AFFF both C8 and C6 type foams. The project program will further evaluate the impact ambient air temperature have on the fire performance of FFF agents. Finally, the optimized foam (expansion, drainage time and shear (flowability)) shall be tested in larger scale fire tests representing “Real World situations appropriate to DoD thus validating the results of the MIL F tests work.
Although CAF is not an absolute drop-in replacement it will make conversion of existing firefighting foam systems and hardware more effective with less change and less impact on training and acceptability. Most systems can remain with the same delivery piping and foam applicator. This could save the Department of Defense (DoD) time and money in the conversion to FFF. However, the greatest benefit is that with a FFF/CAF solution the firefighting performance level may be raised to that equal to AFFF or higher.